The subject invention concept is directed to a resonant laser cavity system for particular use as a resonant cavity for a CO.sub.2 laser. The subject system includes a system formed of three sections defining a pair of opposing discharge tube members being axially aligned. Further, the opposing discharge tube members sandwich a center section formed of an acrylic resin. More in particular, the opposing discharge tube members are each formed of coaxial tubes with the inner tubes being formed of Pyrex glass and the outer tubes formed of an acrylic resin. More in particular, the subject invention directs itself to a mounting mechanism for mirror members including mirror mounting plates having inlet and outlet for cooling oil flow. Still further, the cooling oil flows through the mirror mounting mechanism when the mirror mountings are coupled to laser heads. Further, the cooling oil absorbs a large amount of heat produced by laser discharge in the overall resonant laser cavity system to provide a more efficient and advantageous operational phase.
Still further, the subject system includes mirror members which are held without threaded screw mountings. Further, the system includes a plurality of metal clamp clips positioned on the mirror mounting. More in particular, the invention directs itself to a plurality of clip members which are releasably coupled to the mirror mount by a coil spring which allows displacement along the radial direction to maintain the central portion of the mirror members in an unchanged location during assembly. More in particular, the subject system includes a tubular housing or mirror mount having a slot or groove formed in a cylindrical outer surface to mate with a bar member on a laser head in order that there is no relative motion between the mirror members and the internal O-rings. Thus, there is no necessity for any re-alignment subsequent to optics having been initially aligned.